First [-fifth] Report of Progress of the Geological Survey of Missouri, Volume 1

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Page 227 - coal formations" in all the geological periods, wherever any of the varieties of coal form a principal constituent part of a group of strata. Conformable.
Page 229 - FAULT, in the language of miners, is the sudden interruption of the continuity of strata in the same plane, accompanied by a crack or fissure varying in width from a mere line to several feet, which is generally filled with broken stone, clay, &c., and such a displacement that the separated portions of the once continuous strata occupy different levels.
Page 166 - Halls and Pike counties, of the Hamilton group, in Pike and Marion, and of the vermicular sandstone and shales on North river, seem to possess all the qualities of the very best fire-clays. The quantity of these clays is great, almost beyond computation. No possible demand could exhaust them.
Page 236 - Mineral. Cracks in rocks filled up by substances different from the rock, which may either be earthy or metallic. Veins are sometimes many yards wide ; and they ramify or branch off into innumerable smaller parts, often as slender as threads, like the veins in an animal, and hence their name.
Page 234 - SILT. The more comminuted sand, clay, and earth, which is transported by running water. It is often accumulated by currents in banks. Thus the mouth of a river is silted up when its entrance into the sea is impeded by such accumulation of loose materials. SIMPLE MINERAL. Individual mineral substances, as distinguished from rocks, which last are usually an aggregation of simple minerals.
Page 137 - ... south than in the north, as was to be expected owing to its comparative freedom in the south from marine irruptions. A thickness of 18 feet has been measured in the parish of Earith, but the average thickness is much less. Where beds of silt, etc. are intercalated the individual peat beds measure only from a few inches to a foot and a half in thickness ; and the contemporaneous denudation and breaking up of the peat is often apparent. Along the margins of the peat-land the peat thins out, and...
Page 236 - TUFA, CALCAREOUS. A porous rock deposited by calcareous waters on their exposure to the air, and usually containing portions of plants and other organic substances incrusted with carbonate of lime. The more solid form of the same deposit is called " travertin,
Page 71 - These phenomena have been thus minutely investigated, not merely as interesting scientific facts, but, also, as one of the most useful agricultural features of this preeminently valuable formation ; for upon it, and sustained by its absolutely inexhaustible fertilizing resources, rest the very best farms of the Mississippi and Missouri valleys.
Page 115 - ... which rapidly decomposes when exposed, and leaves the rock full of irregular cavities, and covered with rough, projecting points. These rugged, weather-worn strata crop out in the prairies, and cap the picturesque bluffs of the Osage in Benton, and the neighboring counties. These beds often pass into a homogeneous buff or gray crystalline magnesian limestone, which is frequently clouded with blue or pink, and would make a good fire-rock and building stone. At other places, the strata become compact,...
Page 125 - This is usually a. brown or yellowish-brown fine-grained sandstone, distinctly stratified in regular beds, varying from two to eighteen inches in thickness. The surfaces are often ripple-marked and micaceous. It is sometimes quite friable, though generally sufficiently indurated for building purposes. The upper part is often made up of thin strata of light, soft and porous, semi-pulverulent sandy chert or hornstone, whose cavities are usually lined with limpid crystals of quartz. Fragments of these...

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